Chewing gums generally contain a water-insoluble gum base, as well as sweeteners, natural or artificial flavors, and a variety of additives tailored to provide specific sensory and physical characteristics. The water-insoluble gum base provides the desired chewy and tacky properties to the chewing gum.
Improperly disposed chewing gum cuds can adhere to the ground and other surfaces, where they are typically resistant to environmental degradation. Such gum litter is a nuisance, and its removal can be difficult and expensive.
When a chewing gum is being chewed, it is desirable that the gum maintains its viscoelastic nature. However, the stickiness and elastic properties become undesirable when the chewed gum is discarded. Some researchers have attributed the sticky properties of the chewing gum to the solvent used for dissolving elastomers while making the gum base and proposed excluding the solvent from gum base. For example, U.S. Pat. No. 5,882,702 to Abdel-Malik et al. obviates the need for elastomer solvents by replacing elastomers with a plasticized proteinaceous material such as zein. The incorporation of a plasticized proteinaceous material in chewing gum products, however, often compromises taste and thus can be undesirable from a consumer acceptability standpoint.
Furthermore, gum products that do not stick to teeth or oral prosthetics have been reported in U.S. Pat. No. 4,518,615 to Cherukuri et al. However, these gum products still do not solve the problem of discarded chewing gum cuds, which remain sticky enough to adhere to environmental surfaces and slow to degrade.
There is a need, therefore, for chewing gum compositions that degrade when exposed to environmental factors including sunlight, heat and other physical factors. Also, any solution proposed to address the above problem should not adversely affect the taste, chewy nature, or release profile of the chewing gum compositions.